Lagrangian finite-difference method for predicting green water loadings

Abstract

A meshless CFD method is proposed for numerical simulation of incompressible flows and estimation of hydrodynamic loads during green water events. In this paper, governing equations are described in Finite Differences context, where spatial operators are derived using Weighted-Least Squares. Volume-conservative Lagrangian advection is handled by solving a set of geometrical constraints, while adjusting to moving boundaries represented by triangulated meshes. The validation of the method is performed by simulating four green-water experiments on fixed and moving structures, and comparing the kinematics of flow and hydrodynamic loads during impacts. It is shown that the method accurately reproduces patterns of waves that are wetting the deck, as well as the pressure distribution along the deck. The resulting method intrinsically handles violent fluid–structure interaction with free surface fragmentation, while providing second-order accurate pressure field.